Steps to check computer performance in a Windows 8 / 8.1 computer:
Step 1: Use the run command to open Resource and Performance Monitor.
Open the Run dialog with Windows + R hotkeys, type perfmon / report in the empty box and click OK.
Tip: In this command, there should be a space between “n” and “/”.
Step 2: Wait for the crawl screen to make a diagnosis.
When Resource and Performance Monitor is on, it takes 60 seconds to collect data to generate a system diagnostic report. So you need to wait for the process to complete.
Step 3: Check the System Diagnostics Report and other information.
You can check the System Diagnostics Report, Diagnostic Results, Software Configuration, and other information in the next window.
Meanwhile, the following image with all categories is presented on the screen for your better understanding.